In the field of cardiac surgery, transplantation with homografts become popular recently. Some series of study suggested that tissue viability at the time of transplantation was associated with increased durability. Limiatation of donor
availability led to preservation attemps to increase storage time and ultimately to establish homograft valve banks. For this purpose, cryopreservation is thought to be the best method. And one of the primary objectives of present research
needs
to be
the establishment of satisfactory tests for cell viability.
The purpose of this study is three-fold. Firstly, to confirm the protocols of cryopreservation which are:1) heart procurement:2) valve dissection:3) allograft sterilization:4) pretreatment for cryopreservation:5) storage and 6) thawing. Secondly,
the
effect of low concentration antibiotic solutions is evaluated. Thirdly, as a quantitative test for cell viability. the metabolic assay of fibroblast using radiolabelled glycine(3H-glycine) is practiced. And the results from the two, fresh and
cryopreservation groups, are then compared. In addition, the morphologic changes of fibroblast in these groups are examined with light and transmission electron microscopy.
@ES This study obtained the following conclusions:
@EN 1) The use low concentration antibiotic solution in the preservation procedure was totally effective. However, its cytotoxicity reduced the viability of allografts by 25-33%.
2) In the metabolic assay of viability between the two groups, the viability of fresh group was decreased to 15-19% compared to 45-54% for the cryopreserved group.
3) Under microscopic study, irreversible cellular changes could be seen only in the fresh group.
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